Medical ultrasound transducer having non-ideal focal region

• US 20070035201A1
• Filed: 05/23/2006
• Published: 02/15/2007
• Est. Priority Date: 03/31/2003
• Status: Active Grant

• Current Assignee: Medicis Technologies Corporation
• Original Assignee: LipoSonix, Inc. (Bausch Health Cos., Inc.)
• Inventors: Desilets, Charles, Quistgaard, Jens
• Granted Patent: US 7,766,848 B2
• Time in Patent Office: Days
• US Class Current: 310/311
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61N 2007/0008 Destruction of fat cells
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00

Abstract

A mechanically formed transducer capable of producing a non-ideal focal region is described. The transducer has a plurality of piezoelectric elements suspended in an epoxy and heat molded into a desired shape. One or more shaped irregularities in the transducer provides for a mechanically induced non-ideal focal field without the need for electronic steering or lens focusing. Systems and methods of making the same are also described.

Claims

1. A medical ultrasound transducer having an axis with a front and back surface transverse to the axis, wherein an edge of the surface is axially offset to produce at least one substantially annular 2 π

m phase shift focal region(s) when said transducer is excited, where m is a non-whole number value.

5. The transducer of claim 1 where the transducer incorporates a filler material in front of the transducer or backing material in back of the transducer.

6. The transducer of claim 1, being formed of a single contiguous piezoelectric element.

2. A medical ultrasound transducer having an axis with a front and back surface transverse to the axis, wherein two or more edges of the surface are axially offset to produce a 2 π

m phase shift focal region for each offset when said transducer is excited, where m is any real number.

3. The transducer of claim 2, wherein the two or more edges have the same axial offset value.

4. The transducer of claim 2, wherein the two or more edges have different axial offset values.

7. A method of creating a medical ultrasound transducer having a non-ideal focal region, the method comprising the steps of:

shaping a piezoelectric ceramic into a desired form, the form having a front end and a back end;

dicing said front end create a plurality of elements, said elements being attached to said back end and separated by dicing channels;

filling said dicing channels with an epoxy material and allowing said epoxy to gel;

creating a transducer form by removing said back end such that said elements are separated from one another;

pressing said transducer form into a mold and heating said transducer form such that the epoxy is heated above the B-stage and allowing the resin to cross link and cool in a set shape;

treating at least one surface of the transducer form with a conductive material such that all elements are in contact with said conductive material; and

making a shape irregularity in the transducer form such that the transducer will produce a non-ideal focal region when said transducer is excited.